summaryrefslogtreecommitdiffstats
path: root/include/asm-s390
diff options
context:
space:
mode:
authorChristian Borntraeger <borntraeger@de.ibm.com>2008-04-17 07:46:30 +0200
committerHeiko Carstens <heiko.carstens@de.ibm.com>2008-04-17 07:47:07 +0200
commit9e74a6b8983c2653dd2a6f51e634efa281e95d59 (patch)
tree46a6e3c866a3b7642c6176a9c0ef636267196c0f /include/asm-s390
parent1a5debaaace41f1e91014332e6eedde4499e5638 (diff)
downloadlinux-9e74a6b8983c2653dd2a6f51e634efa281e95d59.tar.bz2
[S390] kernel: show last breaking-event-address on oops
Newer s390 models have a breaking-event-address-recording register. Each time an instruction causes a break in the sequential instruction execution, the address is saved in that hardware register. On a program interrupt the address is copied to the lowcore address 272-279, which makes it software accessible. This patch changes the program check handler and the stack overflow checker to copy the value into the pt_regs argument. The oops output is enhanced to show the last known breaking address. It might give additional information if the stack trace is corrupted. The feature is only available on 64 bit. The new oops output looks like: [---------snip----------] Modules linked in: vmcp sunrpc qeth_l2 dm_mod qeth ccwgroup CPU: 2 Not tainted 2.6.24zlive-host #8 Process modprobe (pid: 4788, task: 00000000bf3d8718, ksp: 00000000b2b0b8e0) Krnl PSW : 0704200180000000 000003e000020028 (vmcp_init+0x28/0xe4 [vmcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3 Krnl GPRS: 0000000004000002 000003e000020000 0000000000000000 0000000000000001 000000000015734c ffffffffffffffff 000003e0000b3b00 0000000000000000 000003e00007ca30 00000000b5bb5d40 00000000b5bb5800 000003e0000b3b00 000003e0000a2000 00000000003ecf50 00000000b2b0bd50 00000000b2b0bcb0 Krnl Code: 000003e000020018: c0c000040ff4 larl %r12,3e0000a2000 000003e00002001e: e3e0f0000024 stg %r14,0(%r15) 000003e000020024: a7f40001 brc 15,3e000020026 >000003e000020028: e310c0100004 lg %r1,16(%r12) 000003e00002002e: c020000413dc larl %r2,3e0000a27e6 000003e000020034: c0a00004aee6 larl %r10,3e0000b5e00 000003e00002003a: a7490001 lghi %r4,1 000003e00002003e: a75900f0 lghi %r5,240 Call Trace: ([<000000000014b300>] blocking_notifier_call_chain+0x2c/0x40) [<000000000015735c>] sys_init_module+0x19d8/0x1b08 [<0000000000110afc>] sysc_noemu+0x10/0x16 [<000002000011cda2>] 0x2000011cda2 Last Breaking-Event-Address: [<000003e000020024>] vmcp_init+0x24/0xe4 [vmcp] [---------snip----------] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'include/asm-s390')
-rw-r--r--include/asm-s390/lowcore.h2
-rw-r--r--include/asm-s390/processor.h7
2 files changed, 9 insertions, 0 deletions
diff --git a/include/asm-s390/lowcore.h b/include/asm-s390/lowcore.h
index 007c8a4941b2..5de3efb31445 100644
--- a/include/asm-s390/lowcore.h
+++ b/include/asm-s390/lowcore.h
@@ -56,6 +56,8 @@
#define __LC_IO_INT_WORD 0x0C0
#define __LC_MCCK_CODE 0x0E8
+#define __LC_LAST_BREAK 0x110
+
#define __LC_RETURN_PSW 0x200
#define __LC_SAVE_AREA 0xC00
diff --git a/include/asm-s390/processor.h b/include/asm-s390/processor.h
index 51d88912aa20..8eaf343a12a8 100644
--- a/include/asm-s390/processor.h
+++ b/include/asm-s390/processor.h
@@ -175,6 +175,13 @@ extern void task_show_regs(struct seq_file *m, struct task_struct *task);
extern void show_registers(struct pt_regs *regs);
extern void show_code(struct pt_regs *regs);
extern void show_trace(struct task_struct *task, unsigned long *sp);
+#ifdef CONFIG_64BIT
+extern void show_last_breaking_event(struct pt_regs *regs);
+#else
+static inline void show_last_breaking_event(struct pt_regs *regs)
+{
+}
+#endif
unsigned long get_wchan(struct task_struct *p);
#define task_pt_regs(tsk) ((struct pt_regs *) \